Improvement in electro-magnetic fire-alarm telegraphs



'm'ryns PATENT OFFICE.

JOHN W. MARTIN, OF ST. JOSEPH, MISSOURI.

Specification forming part of Letters Patent No. 118,033, dated August 15, 1871.

To all whom it may concern:

Be it known that I, JOHN W. MARTIN, of St. Joseph, in the county of Buchanan and State of Missouri, have invented a new and Improved Electro-Magn etic Fire-Alarm Telegraph and I do hereby declare that the following is a full, clear, and exact description thereof, which will enable others skilled in the art to make and use the same, reference being had to the accompanying drawing forming part of this specification, in which the drawing represents a face view of my improved electro-magnetic fire-alarm telegraph.

This invention relates to a new electric fire alarm which is liberated by the motion of the armature, so that whenever the circuit is closed the alarm will be sounded. The invention consists in the combination with a detainingarmature of a drop-lever which liberates the alarm, said lever containing a card or plate marked to show the number of the firedistrict whence the alarm emai'iates.

A in the drawing represents a clockwork pro vided with a clapper, B, which will strike a gong, 0, when the work is set in motion. The anchor to of the escapement is connected with a rod or wire, I), which rests against the edge of a cam or disk, D, pivoted to the case of the clock. As long as the rod 1) rests against the disk, as shown in the drawing, the alarm is locked and cannot move. When, however, the disk is turned to let the end of the rod move into a notch or under a shoulder, c, of the disk the alarm will be liberated and sounded. From the disk D is suspended a wire, (I, with a hook, c, at the lower end. E is the frame of the electric apparatus. It holds an electro-magnet, F, and a pivoted armature, G. The armature, as long as it is clear of the electromagnet, holds a pivoted lever, H, elevated, the end of said lever resting on a projecting pin or shoulder, f, of the armature. As quick as the circuit through the electro-magnet is closed the armature will be attracted thereto and swing clear of the lever H, which will drop upon the hook 6, swing the disk D, and liberate the alarm. The lever H carries a card or plate, g, which is numbered or marked to indicate the district or battery, a wire running from the circuit to the magnet required to attract the armature that holds the lever, with the corresponding number attached.

In order to put up and work my apparatus, screw the alarm-box to a wall or other suitable support; then similarly secure the lower or automatic box far enough below it so that the bar or lever H will drop on the shoulder f of the rod d,- then wind up the alarm. A wire runs from the magnets to a battery located at any suitable point, and another wire runs from thence to one of the alarm-boxes, such as are commonly attached to posts or walls of buildings in cities, and made convenient of access for watchmen, policemen, &c.- The lever placed in such box is also con nected with a circuit-wire which communicates with the aforesaid battery. By pressing down the lever the electric current is sent through the wires that run to the magnets, and the same thus caused to attract the armature and sound the alarm.

Having thus described my invention, I claim as new and desire to secure by Letters Patent The combination of the numbered swinging lever H and supporting armature G with the wire (1 and disk D of the alarm apparatus, all arranged as described.

- JOHN W. MARTIN.

Witnesses PETER REISSLINGER, Gno. P. DIXsoN. 

